In an image forming apparatus such as an MFP and a printer, it is necessary to align the position of a sheet fed from a sheet feeding cassette or a manual sheet feeding tray before conveyance of the sheet to an image forming section in order to obtain high image quality without displacement of an image and without color shift of the image. For the position alignment of the sheet, in most cases, registration rollers are generally provided in a sheet conveyance path to perform positioning and skew correction of the sheet.
When the sheet is fed from the sheet feeding tray to the registration rollers, the registration rollers suspend their rotation and collide with a leading end of the sheet to thereby align the position of the sheet. Then, the registration rollers resume their rotation so that the sheet is conveyed to the image forming section so as to be synchronized with an image formed in the image forming section.
On the other hand, in an image forming apparatus installed in a quiet environment such as an office, it is necessary to reduce noise generated during the operation of the image forming apparatus as sufficiently as possible, so that there is an attempt to reduce noise generated at the time of conveying and positioning the sheet. Therefore, there has been heretofore an apparatus including an elastic guide provided in a curved conveyance path for guiding a sheet to a pair of registration rollers, the elastic guide having an end portion coming into contact with the sheet, the end portion being bent toward a sheet feeding direction to adjust contact between the sheet and the end portion of the guide to thereby reduce noise at the time of registration. An example of such conventional apparatus is disclosed in JP-A-8-026526.
According to the conventional apparatus configured as described in the document, JP-A-8-026526, it is possible to reduce noise generated by contact between the sheet and the end portion of the guide before the sheet reaches the pair of registration rollers and it is also possible to achieve reduction of paper dust produced by the contact. In the sheet conveyance device of the conventional apparatus, however, collision noise is also generated when a leading end of the sheet hits the suspended registration rollers. Particularly in the case where the sheet was stiff and thick, there was a problem that louder collision noise occurred when the sheet collided with the suspended registration rollers.